The following is a part of an upload class in a c# script. I'm a php programmer, I've never messed with c# much but I'm trying to learn. This upload script will not handle anything except images, I need to adapt this class to handle other types of media also, or rewrite it all together. If I'm correct, I realize that

using (Image image = Image.FromStream(file.InputStream))

basically says that the scope of the following is Image, only an image can be used or the object is discarded? And also that the variable image is being created from an Image from the file stream, which I understand to be, like... the $_FILES array in php?

I dunno, I don't really care about making thumbnails right now either way, so if this can be taken out and still process the upload I'm totally cool with that, I just haven't had any luck getting this thing to take anything but images, even when commenting out that whole part of the class...

protected void Page_Load(object sender, EventArgs e)
    {
        string dir = Path.Combine(Request.PhysicalApplicationPath, "files");

        if (Request.Files.Count == 0)
        {
            // No files were posted
            Response.StatusCode = 500;
        }
        else
        {
            try
            {
                // Only one file at a time is posted
                HttpPostedFile file = Request.Files[0];

                // Size limit 100MB
                if (file.ContentLength > 102400000)
                {
                    // File too large
                    Response.StatusCode = 500;
                }
                else
                {
                    string id = Request.QueryString["userId"];
                    string[] folders = userDir(id);

                    foreach (string folder in folders)
                    {
                        dir = Path.Combine(dir, folder);
                        if (!Directory.Exists(dir)) Directory.CreateDirectory(dir);
                    }
                    string path = Path.Combine(dir, String.Concat(Request.QueryString["batchId"], "_", file.FileName));
                    file.SaveAs(path);

                    // Create thumbnail
                    int dot = path.LastIndexOf('.');
                    string thumbpath = String.Concat(path.Substring(0, dot), "_thumb", path.Substring(dot));
                    using (Image image = Image.FromStream(file.InputStream))
                    {
                        // Find the ratio that will create maximum height or width of 100px.
                        double ratio = Math.Max(image.Width / 100.0, image.Height / 100.0);

                        using (Image thumb = new Bitmap(image, new Size((int)Math.Round(image.Width / ratio), (int)Math.Round(image.Height / ratio))))
                        {
                            using (Graphics graphic = Graphics.FromImage(thumb))
                            {
                                // Make sure thumbnail is not crappy
                                graphic.SmoothingMode = SmoothingMode.HighQuality;
                                graphic.InterpolationMode = InterpolationMode.High;
                                graphic.CompositingQuality = CompositingQuality.HighQuality;

                                // JPEG
                                ImageCodecInfo codec = ImageCodecInfo.GetImageEncoders()[1];

                                // 90% quality
                                EncoderParameters encode = new EncoderParameters(1);
                                encode.Param[0] = new EncoderParameter(Encoder.Quality, 90L);

                                // Resize
                                graphic.DrawImage(image, new Rectangle(0, 0, thumb.Width, thumb.Height));

                                // Save
                                thumb.Save(thumbpath, codec, encode);
                            }
                        }
                    }

                    // Success
                    Response.StatusCode = 200;
                }

            }
            catch
            {
                // Something went wrong
                Response.StatusCode = 500;
            }
        }
    }

C# Graphics graphic.DrawImage异常 急 急 急！帮帮忙直接上图了

余道长

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C# Graphics graphic.DrawImage异常急急急！帮帮忙直接上图了